Steam-engine



' 3 Sheets-Sheet 1. N. NILSON.

no Model.)

STEAM ENGINE;

I j Patented Mar. 19, 1889. 1 29.1.

qwitmmoeo (MYYL; O MM.

3 sheets s (No Mod m 7 N NILS STEAM ENGINE ITED NILS NILSON, OF MINNEAPOLIS, MINNESOTA.

STEAM ENGlNE.

SPECIFICATION formingpart of Letters Patent No. 399,771, dated March 19, 1889.

T0 aZZ whom it may concern.-

Be it known that I, NILs NILsON, of Minneapolis,in the county of Hennepin and State of Minnesota, have invented certain Improvements in Steam-Engines, of which the following is a specification.

Theobj ect of this invention is to construct a high-speed steam-engine the working parts of Which will be entirely inclosed and protected and in which the motion imparted by the steam will be transmitted directly to the crank without the use of guides or cross-heads, and the power will be applied at three points equidistant about the central shaft, which allows the steam to exert its full pressure upon the crank at any and all points of the revolution, thus avoiding the deadcenter. In this way I provide an engine which can be made as compact as a rotary engine, but with a direct action upon the crank-shaft.

My invention consists, generally, in the construction and arrangement hereinafter described, and particularly pointed out in the claims.

In the drawings which form a part of this specification, Figure 1 is a vertical cross-section showing the working parts of my improved steam-engine. Fig. 2 is a longitudinal section taken on line a: :30 of Fig. 1. Fig. 3 is a side elevation. Fig. l is a detail showing the cam. Fig. 5 is a cross-section showing a modification. Fig. 6 is a longitudinal section taken on line y y of Fig. 5.

In the drawings, 2 represents the outer case of the engine, preferably made cylindrical in form, and is provided with suitable heads 3 and 4.. A driving-shaft, 5, is preferably journaled in the heads 3 and 4:, and is provided with a crank, 65, preferably formed on the said shaft between the said heads.

8 are division-walls extending from the outer case inwardly toward the center, and they may be formed in one piece with the case. These divisions act as abutments for the oscillating pistons 10, and,together with the said pistons, form three compartments, 7, located within the case 2 equidistant about the drivingshaft. The pistons are provided and supported at one end in one of the abutments 8, and the opposite end is free to swing from the inner wall of the case 2 inwardly toward the center, the

Application filed March 26, 1888. Serial No. 268,497. (No model.)

face of the opposite abutment being fitted to conform to the are described by the said piston. The body of the said piston is preferably curved to correspond to the curve of the inner wall of the case, so that when the pistons are thrown out they will fit closely to this wall, with only sufficient space between them for proper clearance.

The pivoted end of the piston is preferably formed with an enlargement or bearing extending from top to bottom of said piston, and the portion of this hearing outside the body of the piston is made cylindrical in form.

- A corresponding circular recess is formed in the abutment, and the circular end of the piston is introduced into this recess, which embraces a sui'iicient portion of the said end to securely hold it in place against the pressure of the steam, and yet allow the piston to oscillate. The pistons are provided with suitable packing-strips at the sides, which come in contact with the heads 3 and a, and at the ends which slide upon the abutments. By this means a steam-tight joint is made for the steam-compartinents 7.

Each of the pistons is preferably provided with a connectinga'od, 12, secured at one end to the piston by a suitable wrist-pin, and at the opposite end attached by a suitable stub end to the crank-pin.

I prefer to place in the abutinents 8 the induction-ports 16 and the eduction-ports 18, and also a rotary valve, 20, which controls both of these ports. A port, 21, which serves both as an inlet and outlet port, connects the steam-compartment 7 with the valve.

The steam-chest 9 and the exhaust 11 may both be formed in the head 4, and the steamchest will connect with all the steam-ports 16 and the exhaust with all the exhaust-ports 18.

The cavity in the valve 20, upon the side toward the port 21, is made considerably wider than the said port, but as it passes through the said va ve it contracted to the width of the steam or exhaust ports. WVhen this cavity is brought opposite the inductionport 10, a passage is formed through the cavity and the port 21 and. into the compartment 7, and when the valve is turned to bring the cavity opposite the eduction-port 18 the opposite end of the said cavity will still the engine in the opposite direction.

- the forward or backward motion. .65

be open to the port 21, and a passage will be formed from the compartment 7 through the port 21 and the valve 20 to the said eduction-port 18.

The oscillation of the valve 20, to cause the ingress or egress of steam, may be effected by means of a cam, 22, secured to and revolving with the driving-shaft. The valve 20 is preferably provided with a spindle pro.- jecting through the head 3, and a crank or arm, 23, is secured thereto. A stud or antifriction roll, 24, is attached to the outer end of the arm 23, and this roll travels in a groove in the face of the cam 22. The cam 22 is so constructed and located upon the shaft with reference to the crank 5 that the arm 23 will be thrown outward and the steam admitted and the exhaust closed when the crank has reached a point where the connecting-rod 12 and the crank 5 will be in a radial line taken from the center of the shaft. In this position the piston will have reached the limit of its outward throw, and the cam will preferably hold the cam 23 and valve 20 in this position until the cam has completed nearly onehalf arevolution, when the groove in the cam will depress the arm and rotate the valve sufficiently to cut off the steam and open the exhaust.

It will be seen that the steam will follow the piston for a sufficient distance to insure the action of the steam to its full pressure upon the piston and the crank, and that the steam-ports to one compartment will be opened before it is necessary to exhaust the steam from the compartment next in advance, so that the steam begins to act upon each piston before it ceases to act upon the next preceding piston.

I prefer to provide a means for reversing the motion of the shaft, which I do by making a half-revolution of the cam. This is accomplished by allowing the said cam to fit loosely upon the shaft and capable of being moved about it for one-half of a revolution in order to reverse the position of the groove in said cam relatively to the casing 2, so that the valves will be operated and steam admitted to act upon the pistons directly opposite to the direction of the crank. 44 is a collar fast to the shaft and provided with a projection or stop, 45, which engages a corresponding projection upon the cam. WVhen these proj ections are in engagement upon one side, the valves are in position to admit steam and drive the shaft in one direction, and when they are in engagement upon the opposite side the valves will be in position to drive The function of the projections 45 and 46 is to limit the movement of the cam about the driving-shaft and hold the cam in the proper position for the admission of steam for either A clutch, 51, is held upon the shaft by a feather or spline to cause it to revolve with the shaft and allow for its free movement longitudinally thereon. A hub, 47, is formed upon the cam and is provided with a V-shaped recess or opening, 48, upon both .sides. The clutch 51 is provided with a V-shaped projection, 49, which fits the openings 48 in the hub of the cam.

A lever, 50, is fulcrumed below the shaft, preferably upon a projection upon the casing, and is connected to the clutch 51 by suitable pins to allow the clutch to revolve and still be under the control of the lever. When the lever is in the position shown in Figs. 3 and 6, the clutch and cam are in contact and the cam will be driven by the clutch in the direction maintained by the shafts When the lever is thrown out, the clutch is released from the hub of the cam, and the cam, thus released, will stop. The sh aft will continue its movement until the stop 45 makes a half-revolution and strikes the projection on the cam. The position of the valves is now reversed and in position to admit steam for the opposite stroke. If the shaft should not complete the half-revolution and leave the valves only partially reversed, the lever 50 will be operated, causing the V-shaped projection upon the clutch 51 to engage the openings 48 in the hub. These projections, traveling down the inclined surface of the said openings, will force the cam around the shaft and complete the half-revolution necessary to reverse the valves.

An offset, 52, is preferably made at the apex of the projection 49, which is parallel to the shaft, and the inner extremity of the recess 48 is constructed to receive this offset. The purpose of this is to transmit force for driving the cam directly in the line of the motion and relieve the strain, whichwould otherwise fall upon the beveled sides of the projection 49, causing a continual tendency to throw off the clutch.

I prefer to provide an automatic cut-off to control the admission of steam to the engine. The device that I prefer for this purpose is shown in Figs. 5 and 6 of the drawings.

An auxiliary valve, 60, is arranged between the induction-port 16 and the valves 20. The valve 60 is provided with a passage which connects the port 16 with the opening in the valve 20. The valve 60 is adapted to be turned upon its axis, and when this is done the opening through it is partially or wholly closed. Outside of the casing 2 the valve 60 is provided with a stem, 61, and a crank-arm, 63. The arm 63 is connected by a link, 65, with one end of the bell-crank lever 67, pivoted in a suitable support upon the casing. A sliding collar, 69, is arranged upon the crankshaft 5, and is provided with a groove into which the ends of the arms of the bell-crank lever 6'7 project. A collar, 71, is arranged upon the shaft 5 and is secured thereto. Weights 7 3, secured to spring-arms '7 5, are arranged around the shaft 5, the ends of the arms being connected to the ends of the collars 69 and '71.. These weighted arms form a Centrifugal governor which controls the valve 60, so that as the speed is increased the valves are turned to partially close the steam-ports, and as the speed is decreased they are turned to open the ports. By this means the admission of steam to the chambers is automatically controlled.

I claim as my invention- 1. A steam-engine comprising a suitable casing provided With a series of curved abutments, as 8, a crank-shaft mounted in said casing, a series of .three or more pistons pivoted in said casing opposite said abutments,

arms connecting said pistons With said crank shaft, and suitable ports admitting and exhausting the steam and operating to admit the steam to each piston before it ceases to act upon the next preceding piston, substantially as described.

2. The combination, in a steam-engi11e,\vith the casing 2, provided With the abutment-s 8, of the series of oscillating pistons 10, mounted at equidistant points around said casing, the crank-shaft journaled in said casing, arms connecting said pistons With said crank-shaft, the induction and exhaust ports 16 and 18, and the valves 20, controlling said ports, substantially as described.

The combination, in a steam-engine,With the casing 2, provided with the abutments 8, having the ports 16 and 18 arranged therein, of the crank-shaft 5, journaled in said casing, and the series of oscillating pistons l0,pivoted Within said casing and connected with said crank-shaft, substantially as described.

r. The combination, in a steam-engine,With the cylindrical casing 2, provided with the inlet and exhaust ports 16 and 18, of the pivoted piston 10, adapted to fit against the inner curved surface of the casing 2, the crankshaft 5, and the arms 12, connecting said pistons With said crank-shaft, substantially as described.

5. The combination, in a stea1n-engine,with the casing 2, the crankshaft journaled therein, and the oscillating pistons 10, connected with said crank-shaft, of the rotary valves 20, arranged to control the valve-ports and provided with the crank-arms 23, and the cam 22, secured upon the shaft 5 and controlling said valves 20, substantially as described.

6. The combination, in a steanrenginemith the casing 2 and the oscillating pistons 10, of the valves 20, arranged to control the supply of steam to said casing and provided With the crank-arms 23, the grooved cam 22, with which said crank-arms engage, provided With the projection 46, and the collar 44, secured upon said crank-shaft and provided With the projection 4-5, adapted to engage the projection 46, substantially as described.

7. The combination, in a steam-engine, With a series of valves, 20, and the main shaft 5, of the reversible grooved cam 22, mounted upon said shaft and engaging all of said valves, substantially as described.

8. The combination, in a steam-engine, With the crank-shaft 5, of the'series of valves 20, the grooved cam 22, engaging said valve and having a hub, 47, provided with V-shaped recesses 48, the sliding clutch 51, having the V- shaped projections 49, adapted to engage the recesses of the collar 47, and the pivoted lever 50, engaging said collar, substantially as described.

9. The combination, in a steamengine, with the casing 2, the crank-shaft, and the oscillatin g piston, of the rotary valve 60, arranged to control the induction-ports in said casing, and the centrifugal governor mounted on said crank-shaft 5 and connected With said valve (30, substantially as described.

10. The combination, in a steam-engine, With the casing and the crank-shaft mounted therein,of the oscillating pistons connected with said crank-shaft, the induction-ports 16, the exhaust-ports 18, an d the oscillating valves 20, adapted to connect either of said ports With the steam-chambers formed behind said pistons, substantially as described.

In testimony whereof I have hereunto set my hand this 19th day of March, 1888.

NILS NILSON.

In presence of A. 0. PAUL, A. M. GAsKELL. 

